Interface for liquid metal bearing and method of making same

Abstract

An x-ray tube includes a cathode and a target assembly positioned to receive electrons emitted from the cathode. The target assembly includes a target, and a spiral groove bearing (SGB) configured to support the target. The SGB includes a rotatable component having a first surface and a first material attached to the first surface, a stationary component having a second surface and a second material attached to the second surface, the stationary component positioned such that a gap is formed between the first material and the second material, and a liquid metal positioned in the gap, wherein at least one of the first and second materials comprises tantalum.

1. An x-ray tube comprising:
 a cathode; and 
 a target assembly positioned to receive electrons emitted from the cathode, the target assembly comprising:
 a target; and 
 a spiral groove bearing (SGB) configured to support the target, the SGB comprising:
 a rotatable component having a first surface and a first material attached to the first surface; 
 a stationary component having a second surface and a second material attached to the second surface, the stationary component positioned such that a gap is formed between the first material and the second material; 
 a liquid metal positioned in the gap; and 
 spiral grooves in at least one of the first and second materials, wherein the grooves are not in the one of the rotatable component and the stationary component to which the first and second materials are attached; 
 
 
 wherein at least one of the first and second materials comprises tantalum, and wherein a thickness of one of the first and second materials is 1 mm or greater. 
 
     
     
       2. The x-ray tube of  claim 1  wherein the stationary component comprises a center shaft and the rotatable component comprises a sleeve, the sleeve having the target attached thereto. 
     
     
       3. The x-ray tube of  claim 1  wherein the SGB further comprises:
 a third material positioned between the rotatable component and the first material; and 
 a fourth material positioned between the stationary component and the second material. 
 
     
     
       4. The x-ray tube of  claim 3  wherein one of the third material and the fourth material comprises a braze material. 
     
     
       5. The x-ray tube of  claim 1  wherein the liquid metal comprises one of gallium and an alloy of gallium. 
     
     
       6. The x-ray tube of  claim 1  wherein one of the rotatable component and stationary component comprises one of refractory metal or refractory metal alloys, a superalloy, Kovar®, a tool steel, a FeNi alloy, a maraging steel, Glidcop® and stainless steel. 
     
     
       7. The x-ray tube of  claim 1  wherein one of the rotatable component and the stationary component comprises an iron-based material having a chromium content less than 10%.